What and when babies first eat may affect diabetes risk

Infants at risk of type 1 diabetes who receive their first solid foods between ages 4 months and 6 months appear less likely to develop the condition than others given solid food before or after that time window, a new study finds.

Type 1 diabetes, which can strike children at any age, occurs when an aberrant immune reaction kills cells in the pancreas, requiring a person to take insulin shots. Two studies in 2003 found an association between early first foods and the presence of rogue antibodies, a warning sign of type 1 diabetes. The new findings go an important step further, tracking babies long enough to see who developed diabetes, says Kendra Vehik, an epidemiologist at the University of South Florida in Tampa.

The new study, which appears July 8 in JAMA Pediatrics, included 1,835 children in the Denver area who had reached at least age 7. They were at high risk because they either carried a genetic trait that increased their risk for the disease or had a parent or sibling with type 1 diabetes. Of the 53 children with diabetes, 28 had had their first exposure to solid food before age 4 months, roughly double the risk of kids who had started eating food at age 4 to 6 months.

Babies who had eaten their first foods later than age 6 months had a tripled risk. But very few children were started on solid foods that late, so study coauthor Jill Norris, an epidemiologist at the University of Colorado in Denver, says she’s unsure of the reliability of that risk.

The study also suggests an increased risk from introducing fruit before 4 months and rice and oats after 6 months, but those findings aren’t statistically strong enough to implicate the timing of those particular foods in diabetes risk, Norris says.

More interesting, she says, was a finding that babies who were breast-fed when they were introduced to wheat were about half as likely to develop type 1 diabetes as were infants not breastfed while starting on wheat. Researchers know that infants’ immune systems are still a work in progress. One hypothesis holds that first solid foods might overstimulate the immune system, Norris says. How that would affect the complex immune reaction that causes type 1 diabetes, or whether breast-feeding might prevent it in some cases, remains unknown.